Gauges with moving pointers have been known and used for many years. Some cluster gauge designs, for example speedometer or tachometer gauges in the dashboard of a motor vehicle, have a display located in a center of a gauge with a scale disposed around a periphery of the display. As a further example, the display can be used for fuel, computer, navigation, status warnings, safety features, telephone controls, and many other possible applications.
To avoid the pointer, or any supporting member for the pointer, overlying the display, a number of approaches have been devised for driving a pointer around the scale at the periphery of the gauge. U.S. Pat. No. 6,484,663 describes a ring gear and pinion drive arrangement. U.S. Pat. No. 7,159,534 discloses the use of a hook-shaped pointer with a motor mounted behind the display. A belt drive is used to move a display pointer in Japanese patent application JP 20050432787. It is known from International Pat. Appl. No. WO 20041068077 to form the image of a pointer on the display, and it is also known to reflect the image of a display in a lens in front of the gauge.
Prior art gauges and methods have various limitations, including the space needed to fit the mechanisms in or the visibility of imaged pointers in adverse lighting conditions. Typically, prior art gauges include scale designs that are limited to circular arcs.
It would be desirable to develop a gauge that minimizes a space requirement for the pointer and scale, while maximizing design option beyond circular shapes.